WAXD和DSC法计算β-PP中β晶相对含量的对比研究  

Comparative Study on Calculation for Relative β Crystal Content of β-PP by Using WAXD and DSC Method

作　　者：朱文利[1,2] 刘祯[1,2] 朱定见[1,2] 

机构地区：[1]湖北文理学院机械与汽车工程学院,湖北襄阳441053 [2]汽车零部件制造装备数字化湖北省协同创新中心,湖北襄阳441053

出　　处：《工程塑料应用》2015年第5期83-87,共5页Engineering Plastics Application

基　　金：国家自然科学基金项目(51403059);湖北省自然科学基金项目(2014CFB456);襄阳市科技计划研究与开发项目(襄科业[2013]66号)

摘　　要：采用β成核剂对3种实验室自制的聚丙烯(PP)分别进行熔融共混制成含β晶的PP(β-PP)试样,并经相同的结晶条件对试样进行处理,分别用广角X射线衍射(WAXD)仪和差示扫描量热(DSC)仪计算试样中的β晶相对含量。利用分峰软件Peakfi t对WAXD衍射峰进行处理,根据α晶和β晶的衍射峰强度计算了β晶相对含量;利用TA Universal Analysis软件对DSC熔融曲线进行分析,根据α晶和β晶的熔融峰面积计算了β晶相对含量。计算结果显示,用WAXD法计算的3种β-PP的β晶相对含量分别为48%,43%和18%,而用DSC法计算的分别为27%,11%和5%。用WAXD法测试结晶度时,试样无需受热,而用DSC法时,β晶在加热过程中容易发生β–α转变,导致β晶数量减少、α晶数量增加从而引起计算的β晶相对含量较实际值偏低。The β-PP samples were made by melt-blending three kinds of self-made polypropylene materials with a β nucleating agent. The samples were treated under the same crystallization conditions and the relative β crystal contents were measured by utilizing wide angle X-ray diffraction spectrum （WAXD） and differential scanning calorimeter （DSC）, respectively. The peak-separating software Peakfit was used to deal with WAXD diffractive peaks and the relative β crystal content was calculated according to the intensity of diffractive peaks for α and β crystals. The software TA Universal Analysis was used to analyze DSC melting curves and the β relative crystal content was calculated according to the area of melting peak for αand β crystals. The results show that the relativeβ crystal content of the three β -PP samples calculated by WAXD method is 48%, 43% and 18%while that calculated by DSC method is 27%, 11% and 5%, respectively. The samples are not heated when WAXD method is employed, however, when DSC method is employed, β-α transition happens during the heating process, resulting the calculated relative βcrystal content value was smaller than the real one due to the decreased β crystal content but increased α crystal content.

关 键 词：聚丙烯 β晶相对含量计算 广角X射线衍射法 差示扫描量热法 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]